The present invention relates to improvements in an evaporator for an automotive air-conditioner.
Generally, an automotive air-conditioner comprises an evaporator for cooling air employed for air conditioning by evaporating refrigerant in the evaporator. Various types of evaporators have been proposed and in practical use. Japanese Patent Publication (Heisei) No. 7-39895 discloses an evaporator constituted by a plurality of heat-transfer tube plates made from a pair of pressed metal plates. As shown in FIGS. 22 and 23, this conventional evaporator 101 is constituted by a core 111 having a plurality of U-shaped refrigerant passages and corrugated fins, and first to fourth tank passages 103 to 106. The core 111 is separated into first and second cores. Refrigerant is supplied from a refrigerant inlet 107 to the first tank passage 103, and flows through the U-shaped refrigerant passages 102a of the first core, the second tank passage 104, the third tank passage 105, the U-shaped refrigerant passage 102b of the second core in the order of mention. Thereafter, the vaporized refrigerant due to heat exchanger in the core 111 flows out through a refrigerant outlet 108 installed to the fourth tank passage 106. This conventional evaporator 101 is arranged to provide choke portions 112 in the first and third tank passages 103 and 105 so that the refrigerant is equivalently distributed to the heat-transfer tube elements.